The results showed that the top genes positively associated with PC1 included RBP4, SLC27A5, and PCK2, all of which were known tumor-related genes and correlated with cancer patients’ survival (Anderson and Stahl, 2013; Leithner et al., 2014, 2015; Balsa-Martinez and Puigserver, 2015). Here, RBP4 is linked to neoplasm.